The primary goal of this work is to contribute to the investigation and solution of basic medical problems by the application of chemical, physical and biological methods. This goal is being pursued by studies of the biology and biochemistry of murine tumor cells with emphasis on cancer metastasis. Studies were begun several years ago to determine whether one or more specific gene products are required to confer on certain tumor cells the properties needed for cancer metastasis. Promising preliminary results obtained with NIH 3T3 cells transfected with one of several oncogenes were reported previously. This work has been suspended temporarily because of other priorities. Other lines of work in the area of cancer metastasis, such as the interactions of tumor cells with basement membrane components and other biological materials, the nutrition of tumor cells, and the effects of the treatment of tumor cells with chemicals and biologicals on metastatic potencies, are also to be resumed when the priorities imposed by other responsibilities permit. Meanwhile, and several lines of murine tumor cells, which have been used in the past and which are to be used in the future, are being maintained in mice and their metastatic potencies monitored. During this period C. M. Foltz has been serving as NIDDK Safety Officer, Building 8/8A Occupant Emergency Coordinator and Safety Officer, and as Building 8/8A, Manager; much of his work has been in those areas.